On Green Fairs and Green Fairies

Adobe regularly has a Green fair, which is like a small version of the Melbourne Sustainable Living fair, or the Fort Collins New Belgium renewable energy festival, or the Pennsylvania... you get the idea.

There was a person selling LED strips in the same form factor as a 60cm fluoro. She had fixtures, one with a normal fluoro, one with a high colour temp (10000K) LED array and one with two lower temperature arrays (say 6500K and 5300K). They were an impressive idea, but I'm wary of such demonstrations as they perhaps rely on the concentration of the light from LEDs to give the impression of greater luminous efficiency than they really have (they claimed 36Lm/W which is considerably below than the 80Lw/W for an off the shelf light - confirming my doubts). Of note is that each light fixture had a killawatt meter showing that two led strips had the same power consumption as one fluoro. One of the meters was showing 'F' and she said she had no idea what the problem was. I swapped them over to see whether it was the light or the meter that was wrong, but that was sufficient to restore reading. She thought I was a magical genius :)

Later, Grayson asked my opinion of a silver colloid based washing machine. Silver colloid is a known antibacterial agent (and turns your skin blue!), but I don't know how it would actually clean.

Also for sale was a magical 'energy saver' box that you plugged in between the grid and your house. Somehow, magically, it saved power. The demonstrator had a little test rig set up with a magical box, a squirrel cage motor, two moving coil meters and two switches (not magic and more magic :). One switch turned the motor on and off, the other inserted and removed the magic box.

Her demonstration was to turn the motor on, and gee golly, both meters went to 11. Then she would turn on the magic device, and the meter purporting to be input power would drop by about 20%. She would then carefully turn the motor off and then disconnect the magic box (I never asked to try turning the motor off, then the magic device, I wonder why she was so careful about that).

My thought was, 'hmm, probably power factor correction with a naïve AC current meter rather than proper integrated power'. Well it occurred to me that there was a supply of killawatt meters back at that previous display. So I borrowed one. By this stage I had a small crowd. So we plugged the test rig into the killawatt meter (I was most impressed by the sales ladies acceptance of my attempted debunking). with nothing on, it drew 0W. with just the motor on, 83W. with the magical box, 84W. So the magical box actually used about 1% extra power. And the killawatt meter happens to be able to report the power factor... sure enough, with just the motor, pf = 0.5. With the magical box, pf = 0.86.

She was careful to not let me measure the power draw with the magical box but without the motor. I didn't want to push the point and make a scene. She agreed that all the device did was power factor correction. I respect her candour, but wonder whether things like this are harmful to good green design by diverting money from higher payoff changes.




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